Fluid impeller structure



April 24, 1956 A. T. GREGORY ETAL 2,743,053

FLUID IMPELLER STRUCTURE Original Filed Oct. 27, 1950 5 Sheets-Sheet l INVENTORS ALFRED T. GREGORY KEN NETH A. BROWNE THEIR ATTORNEYS FIGJ A ril 24, 1956 A. 'r. GREGORY EI'AL 2,743,053

FLUID IMPELLER STRUCTURE Original Filed Oct. 27, 1950 5 Sheets-Sheet 2 INVENTORS ALFRED T. GREGORY KENNETH A.- BROWN W.WFEMTM TTORNEYS April 24, 1956 A. T. GREGORY ETAL 2,743,053

FLUID IMPELLER STRUCTURE Original Filed Oct. 2'7, 1950 3 Sheets-Sheet 5 I NVENTORS FIGS. QE JSFSSVSLE a W, M,MEM

THEIR ATTORNEYS shaped diffuser vanes 7' welded to casing 1 and wall 6', as shown in Figs. 1 and 3. The forward end of the tubular inner wall 6 lies coextensivcly and in axial alignment with the rear end of the impeller face segments 6, so that the air can flow smoothly without turbulence from the impeller into annular space 4'. Similarly, the rearward end of the inner wall 6' converges toward the axis of the turbine shaft 15. The flow of air diverging in that direction is aided by annular deflector 5, which is welded to the interior surface of casing 1, as is shown especially in Fig. 3. The annular stream of compressed air flowing between the deflecting and guiding surfaces 5 and 6 enters the combustion chambers or burners, not shown.

Proper functioning of the engine and high speed rotating parts, including the impeller and the turbine, requires satisfactory balancing of these parts. This is readily accomplished according to the invention without expensive machining operations by slotted sheet metal balance ring 48 secured to the front end of turbine shaft as is shown in Figs. 1 and 3. In order to achieve the desired balance of the rotor assembly, the peripheral teeth or spokes formed on balance ring 48 by the slots are simply broken off at the points indicated by balancing apparatus as being in unbalance.

Operation of the gas turbine impeller of this invention will be readily understood from the foregoing description of the construction thereof, and although a preferred embodiment of the invention has been illustrated and described herein, it is to be understood that the invention is not limited thereby or thereto, but is susceptible of changes in form and detail within the scope of the appended claims.

a We claim:

1. In a gas turbine engine, the combination of a hollow compressor casing, a rotor hub journalled therein, substantially radial blades having elongated inner edges secured to said hub, outer rearwardly diverging edges substantially complemental to the shape of the casing and leading and trailing edges, and web segments connected to and interposed between successive blades and extending substantially the axial length of said blades, said web segments diverging outwardly relative to the axis of said 3. The gas turbine engine set'forth in claim 1, comprising a substantially tubular wall mounted in substantial alignment with said web segments within said casing and forming an annular air passage therewith, and diffuser vanes extending substantially radially across said air passage and spaced apart angularly around said annular air passage.

4. In a gas turbine engine, the combination of a hollow compressor casing, a rotor hub journalled therein, longitudinal ridges on said hub, substantially radial blades having elongated inner edges secured to the outer edges of corresponding ridges, said blades having narrow leading edges, wider trailing edges and rearwardly diverging outer edges adjacent and complemental to said casing, webs connected to and interposed between successive blades and extending substantially the axial length of said blades, said web segments diverging outwardly relative to the axis of said hub from the inner ends of the leading edges of the blades adjacent the hub to points adjacent to but spaced inwardly from the outer ends of the trailing edges of said blades, and means extending substantially radially inwardly from the axial ends of said webs to the hub to enclose the space within said webs against windage and form a hollow core having an outer and reinforcing periphery joined to the blades at about their middles.

5. In a gas turbine engine, the combination of a hollow casing, a rotor hub journalled therein, longitudinal ridges on said hub, substantially radial blades secured along their inner edges to the outer edges of said ridges, each blade also having a leading edge, a trailing edge and an outer edge complemental to at least a portion of the interior of said casing, said trailing edge being longer than the leading edge and the outer edge being inclined relative to the inner edge, and webs connecting successive blades in circular alignment, said webs extending from about the junction of said inner and leading edges to the rear edge inwardly of but adjacent to the junction of the outer and trailing edges to form an annular surface flaring outwardly from the inlet edges of the blades to their outer edges and being reversely curved in longitudinal section.

References Cited in the file of this patent UNITED STATES PATENTS 1,153,872 Matsler Sept. 14, 1915 2,539,960 Marchant et al Jan. 30, 1951 FOREIGN PATENTS 595,643 Great Britain Dec. 11, 1947 604,378 Great Britain July 2, 1948 

